Many stereoscopes including folded stereoscopes have been proposed. In one conventional type, the folded stereoscope is assembled into a box shape and in another, the stereoscope has portions which require paste for connection between the portions as disclosed the above mentioned Japanese Utility Model Publication 22276/1977. In these folded stereoscope, production must be done manually due to the difficulty in automation of mass production. Consequently, the cost of manufacture is high. Further, the body of these conventional stereoscope occupies much space and cannot be easily put into a flat configuration when folded.